Koop

Thanks! Well, if the Seeed Studio (I hate the way that the name is spelled) valves don't work, then I will make a mental note about that. However, their valves are looking good in theory, and a recent trip to Bunnings (My local hardware store) showed that I could get 20mm outside diameter (I would say roughly 18mm inside diameter) PVC pipe which I could file down to fit the valves from Seeed Studio. Do you reckon the water pressure that will build up over time could do some damage to the solenoids, the pipe or the hose?

Koop

Pantonvich, thanks for the link, but I'm still going to go for the Seeed Studio valves because I've worked most things out, and they seem perfect and as cost-effective as possible (I can run almost everything off my one power supply, etc.) But thanks anyway